Friday 11th - Sunday 20th May, Edinburgh
Infrasound
Para.Science members conducted groundbreaking research beneath Edinburgh's haunted streets as part of the 2007 Mary King's Ghost Fest.
Using specialised equipment designed and manufactured by team co-founder Steve Parsons, unsuspecting members of the public were blasted with Infrasound to test the idea that this powerful but inaudible sound energy might be responsible for some of the ghostly encounters reported inside Mary King's Close.
Click here to see the prelimiary results from this exciting experiment
A pair of massive 3 metre long sound generators developed from an earlier design by the National Physical Laboratory were used to generate infrasonic frequencies below 20Hz. The system known as ARIA - Acoustic Research Infrasound Array was first used at the "Silent Sound" concert performance held at Liverpool's historic St. George's Hall on September 14th , 2006. It has also featured in a Discovery Channel 2 hour long Infrasound special "The Tiger's Roar" first shown on February 11th 2007.
ARIA is capable of delivering Infrasound as low as 12Hz at an earth-shaking 140dB although for the experiments at Mary King's Close it was running at much lower sound levels.

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Experiment
A team of Para.Science researchers led by co-founder Ann Winsper collaborated with Parapsychologist Dr. Ciaran O'Keeffe to study the psychological and physiological effects on members of the public touring the close to try and determine if exposure to Infrasound may be responsible for reported incidents of paranormal like experiences.
This is a unique experiment prompted by the work of the late Vic Tandy from Coventry University. He produced a series of papers putting forward the hypothesis that infrasound may cause some individuals to have unusual experiences that they may subsequently believe to be paranormal (Tandy & Lawrence, 1998; Tandy, 2000). Subsequent papers (e.g. O'Keeffe & Angliss, 2004; Wiseman et al, 2003) have examined the link either as one of several proposed links (e.g. Infrasound associated with emotional response to music) or merely put forward a tentative link (e.g. Fielding & O'Keeffe, 2006).
As part of the 2005 Ghost Fest Vic Tandy undertook ambient Infrasound measurements at several areas within Mary King's Close and discovered that in two of the areas said to be haunted, infrasound energy was found to be around 20dB higher than in other parts of the Close. He identified key Infrasound frequencies at 10Hz, 13Hz and 17Hz as being present. Using a second set of equipment again designed and manufactured by Steve we aimed to repeat Vic's measurements and also to extend them to see if it is possible to identify the sources of the ambient Infrasound. This equipment is designated ARID - Acoustic Research Infrasound Detector and is the partner system to ARIA.
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ARID
ARID is unique and purpose designed as for its role in paranormal research. It provides the ability to display and measure in real-time any audio frequency from 100Hz to 1Hz using a powerful spectrum analyser. It also permits simultaneous recordings of the very low frequency sound and Infrasound to be made, allowing for storage further analysis to be done at a later date. ARID has been designed to be portable and can be used at almost any location both indoors or out.
Currently, ARID is being used in an extended series of Infrasound measurements at a range of haunted and control sites around the UK to establish for the first time a proper series of baseline Infrasound data that can be used to support further research into the hypothesised link between Infrasound and the paranormal. This series of Infrasound measurements is partially funded by a generous grant from The Society for Psychical Research.

Details of this year's Ghost Fest can be seen at the official Ghost Fest site (click logo above)
References
Fielding, Y. & O'Keeffe, C. (2006). Ghost Hunters: A guide to investigating the paranormal. London: Hodder & Stoughton.
O'Keeffe, C. & Angliss, S. (2004). The subjective effects of infrasound in a live concert setting. Paper presented at the International Conference on Interdisciplinary Musicology, Graz, Austria. Sponsored by European Society for the Cognitive Sciences of Music.
Tandy, V. & Lawrence, T. R. (1998). The Ghost in the Machine. Journal of the Society for Psychical Research, 62, 360-364.
Tandy, V. (2000). Something in the Cellar. Journal of the Society for Psychical Research, 62(3), 129-140.
Wiseman, R., Watt, C., Stevens, P., Greening, E. & O'Keeffe, C. (2003). An Investigation into alleged hauntings. British Journal of Psychology, 94, 195-211.